Now there is this:
Association of Vitamin D Levels With Outcome in Patients With Melanoma After Adjustment For C-Reactive Protein. Fang, Sui, Wang, et al. J Clin Oncol. 2016 Mar 21.
To evaluate for an association between 25-hydroxyvitamin D levels (vitamin D) and outcome measures in patients with melanoma after evaluation is controlled for systemic inflammatory response (SIR) on the basis of simultaneous C-reactive protein (CRP) measurement. Plasma samples from 1,042 prospectively observed patients with melanoma were assayed for vitamin D and CRP. The associations of demographics and CRP with vitamin D were determined, followed by a determination of the association between vitamin D and stage and outcome measures from the date of blood draw. The vitamin D level was considered sufficient if it was 30 to 100 ng/mL. Kaplan-Meier and Cox regression analyses were performed. The median vitamin D level was 25.0 ng/mL. The median follow-up time was 7.1 years. A lower vitamin D was associated with the blood draw during fall/winter months, older age, increased CRP, increased tumor thickness, ulcerated tumor, and advanced melanoma stage. On univariate analysis, lower vitamin D was associated with poorer overall survival, melanoma-specific survival, and disease-free survival. The effect of vitamin D on these outcome measures persisted after adjustment for CRP and other covariates. Multivariable hazards ratios per unit decrease of vitamin D were 1.02 for OS, 1.02 for MSS, and 1.02 for DFS. Lower vitamin D levels in patients with melanoma were associated with poorer outcomes. Although lower vitamin D was strongly associated with higher CRP, the associations of lower vitamin D with poorer OS, MSS, and DFS were independent of this association. Investigation of mechanisms responsible for these associations may be of value to patients with melanoma.
For what it's worth. I happen to take 2000 units of Vitamin D daily. Not saying you should....just say'n I do. - c